DE102008000091B4 - Device for controlling an illumination angle of headlamps of a vehicle - Google Patents

Abstract

A device (100) for controlling a lighting angle of headlamps (50L, 50R) installed in a vehicle, comprising:
a position detection device (30) configured to detect a current position of the vehicle,
a memory device (32) configured to store road information showing a road on which the vehicle is currently traveling,
curve keeping means (30) configured to obtain from the present position detected by the position detecting means (30) and the road information read from the storage means (32) a curve of the road ahead of the vehicle is positioned, and to get a radius of the curve,
a distance obtaining means (30) configured to obtain a distance from the current position to a starting point of the curve on the basis of the current position and the road information;
curve determining means (30) configured to determine whether or not the curve is an S-shaped curve based on the road information;
a line shape setter (30) configured to set line shape information showing a line shape of the S curve in response to determination results of the curve determination means (30);
an angle calculator (10) configured to calculate an illumination angle of the headlights based on the radius of the curve, the distance, and the line shape information, and
a controller (20) configured to control the illumination angle of the headlights (50L, 50R) based on the calculated illumination angle.

Description

BACKGROUND OF THE INVENTION

[Technical Field of the Invention]

The present invention relates to a headlamp illumination angle control apparatus for controlling an illumination angle of headlamps installed in a vehicle.

[Related Art]

A technique of this kind is well known, as disclosed, for example, in Japanese Patent Publication JP 2003-072460 A is disclosed. The technique disclosed in this document uses a wheel speed detected by a wheel speed sensor for detecting a wheel speed of the vehicle and a steering angle detected by a steering angle sensor for detecting a steering angle of the steering wheel of the vehicle. Based on the wheel speed and the steering angle, the illumination angle of the headlights is controlled such that a point, which is likely to be reached by the vehicle after a predetermined time interval has elapsed, falls within an area illuminated by the headlights of the vehicle.

It is true that, in the above-mentioned headlamp illumination angle control device, the illumination angle of the headlamps is controlled such that the point that is likely to be reached by the vehicle after the lapse of a predetermined time interval falls within an area illuminated by the headlamps of the vehicle. However, since the headlight illumination angle is determined on the basis of the wheel speed and the steering angle, the timing for actually starting a control of the headlight illumination angle just before the time when the vehicle is actually turning into a curve, i.e., falls. it falls to a point after the vehicle has reached a point that is quite close to a starting point of the curve. In general, a driver of the vehicle visually confirms the depth, sharpness, or the like of a curve in advance, before the steering wheel is turned, or immediately before the vehicle actually enters the curve. Accordingly, when considering a drive at night, an attempt to confirm the breadth or sharpness of a turn just before the vehicle actually enters the turn ends unsuccessfully, as the curve through the headlights is still to be illuminated. Thus, during night driving, it is difficult for a driver of the vehicle to visually confirm in advance the line shape of a turn in which the vehicle is about to enter.

The publication DE 10 2007 000 601 A1 describes a device for controlling pan angles of vehicle headlights, wherein the pan angle of the lights in a lateral direction of the vehicle is variable. A target turning angle of the headlights is determined based on, for example, road map data of the road ahead of the vehicle, and a control start point is determined based on the current position information and the road map data. The swivel angle is controlled in response to a state to the target swivel angle, in which the current position of the vehicle has reached the control start point. Route shape related information and a curve direction of the road ahead of the vehicle are determined. Control of the swivel angle to the target swivel angle is prevented when a direction of the specific target swivel angle does not coincide with the turning direction of the road, even in a case where the vehicle has reached the control start point.

BRIEF SUMMARY OF THE INVENTION

The present invention has been made in view of the circumstances described above, and has an associated object to provide a headlamp illumination angle control apparatus which enables a driver of the vehicle to obtain in advance a more accurate visual confirmation of a line shape of a curve in which the vehicle is about to be be retracted, execute.

This object is achieved by a device for controlling an illumination angle of headlamps according to claim 1, 11 or 21. Advantageous developments are specified in the respective dependent claims.

In order to achieve the above-mentioned object, one form of the present invention includes an apparatus for controlling an illumination angle of headlamps mounted in a vehicle, comprising: a position detecting means for a current position of the vehicle, a storage means for storing road information including a vehicle Road on which the vehicle is currently driving, a curve retainer for obtaining, from the current position and the road information, a curve of the road, which is positioned in front of the vehicle, and for obtaining a radius of the curve, a distance maintaining device or Distance detecting means for obtaining a distance from the current position a starting point of the curve on the basis of the current position and the road information, a curve determining means for determining whether the curve is an S-shaped curve or not, based on the road information, a line shape setting means for setting line shape information having a line shape of the S A graph shows, in response to determination results of the curve determining means, an angle calculating means for calculating a lighting angle of the headlights based on the radius of the curve, the distance and the line shape information, and a controller for controlling the lighting angle of the headlights on the basis of the calculated lighting angle.

In the above-described configuration, the illumination angle of the headlights is not calculated based on the actual wheel speed or the actual angle as in the above-described prior art, but is calculated on the basis of the information given in advance by the above various facilities. Thus, the illumination angle of the headlights can be controlled well in advance of the entrance of the vehicle into a curve in accordance with the timing of the driver of the vehicle to visually confirm the width or sharpness of the curve, rather than immediately before the actual entrance of the vehicle to be controlled in the curve.

For example, in the case where the curve in which the vehicle is about to enter has a line shape that rotates successively in different directions, such as an S-shaped curve, the illumination angle of the headlights will be in accordance with the line shape of FIG controlled near-edge curve. Then, the illumination angle of the headlights is quickly controlled in accordance with the line shape of the following curve. In the conventional headlamp illumination angle control apparatus mentioned above, the timing for actually starting a control of the illumination angle of the headlamps immediately before the actual entrance of the present vehicle into the curve falls. Accordingly, this may delay the timing for illuminating the headlights to visually confirm the line shape of the near-side curve, possibly setting the driver unable to visually confirm the line shape of the following curve. In this regard, the above-mentioned configuration can enable calculation of the illumination angle of the headlights, not only by watching over the line shape of the near-side curve, but also by the line shape of the following curve, since the line shape information detected by the line shape information detection device becomes the result of the determination whether the curve is an S-shaped curve or not. Thus, the driver of the vehicle can make a more precise visual confirmation of the line shape of the curve in which the vehicle is about to retract.

In order to achieve the above object, another aspect of the present invention includes an apparatus for controlling an illumination angle of headlamps installed in a vehicle, comprising: a vehicle position current position detecting device, a road information storing device show a road on which the vehicle is currently running, a curve retainer for obtaining, from the current position and the road information, a curve of the road, which is positioned in front of the vehicle, and for obtaining a radius of the curve, a distance obtaining device for obtaining a distance from the current position to a starting point of the curve on the basis of the current position and the road information, a gradient obtaining means for obtaining gradient information indicative of a gradient of the vehicle in a direction z along which the road continues, an angle calculator for calculating an illumination angle of the headlamp based on the radius of the curve, the distance and the gradient information, and a controller for controlling the illumination angle of the headlamps based on the calculated illumination angle.

In the above-described configuration, the illumination angle of the headlights is not calculated based on the actual wheel speed or the actual steering angle, as in the aforementioned prior art, but is calculated on the basis of the information provided in advance by the various above Facilities are recorded. Thus, the illuminance angle of the headlights can be controlled well in advance of the entrance of the present vehicle into a turn in accordance with the timing for the vehicle driver to visually confirm the width, sharpness or the like of the curve, instead of being controlled immediately before the vehicle actually enters the curve.

For example, in the case where the curve in which the present vehicle is about to enter has a slope, the distance illuminated by the headlights of the present vehicle will be shorter than in the case of a flat road. In this regard, since the above-described configuration of the illumination angle calculation unit enables To calculate illumination angles of the headlights on the basis of the gradient information, the illumination angle control of the headlights to be performed in consideration of the gradient of the road. Thus, the vehicle operator can make a more precise visual confirmation of the line shape of the curve in which the vehicle is about to retract.

A still further form of the present invention includes an apparatus for controlling an illumination angle of headlamps installed in a vehicle, comprising: a position detecting means for a current position of the vehicle, a storage means for storing road information showing a road on which Vehicle is currently driving, a curve obtaining means for obtaining from the current position and the road information, a curve of the road, which is positioned in front of the vehicle, and for obtaining a radius of the curve, a distance obtaining means for obtaining a distance from the current position to a starting point the curve based on the current position and the road information, a curve determining means for determining whether the curve is an S-shaped curve or not based on the road information, a line shape setting means for setting Lini information indicating a line shape of the S-curve in response to determination results of the curve determining means, gradient obtaining means for obtaining gradient information showing a gradient of the vehicle in a direction along which the road continues, an angle calculating means for calculating an illumination angle of the headlights based on the radius of the curve, the distance, the line shape information and the gradient information, and a controller for controlling the illumination angle of the headlights on the basis of the calculated illumination angle.

In the above-described configuration, the illumination angle of the headlights is not calculated based on the actual wheel speed or the actual steering angle, as in the aforementioned prior art, but is calculated on the basis of the information provided in advance by the various above Facilities are recorded. Thus, the illuminance angle of the headlights can be controlled well in advance of the entrance of the present vehicle into a turn in accordance with the timing for the vehicle driver to visually confirm the width, sharpness or the like of the curve, instead of being controlled immediately before the vehicle actually enters the curve.

In the case where a curve, in which the present vehicle is about to enter, has a line shape that curves successively in different directions, such as in the case of an S-shaped curve, the illumination angle of the headlights will be in accordance with FIG Controlled line shape of the near-side curve. Then, the illumination angle of the headlights is quickly controlled in accordance with the line shape of the following curve. In the conventional headlight illumination angle control apparatus mentioned above, the timing for actually starting a control of the illumination angle of the headlights just before the actual entrance of the present vehicle into the curve falls. Thus, this may delay the timing for illuminating the headlamps for the driver to visually confirm the line shape of the near-side curve, possibly rendering the driver unable to visually confirm the line shape of the following curve. Further, it has been confirmed by the inventors that in the case where a curve in which the present vehicle is about to enter, for example, a slope, the distance in front of the vehicle, which is illuminated by the headlights, is shorter than in the Fall of a flat road.

In this regard, the configuration described above can enable calculation of the illumination angle of the headlights, not only the line shape of the near-side curve being perceived, but also the line shape of the following curve, since the line shape information detected by the line shape information detecting device is the result of the determination thereof whether the curve is an S-shaped curve or not. The above-mentioned configuration can also enable control of the illumination angle of the headlights in consideration of the gradient of the road, since the illumination angle calculating means calculates the illumination angle of the headlights on the basis of the gradient information. Thus, the vehicle operator can make a more precise visual confirmation of the line shape of the curve in which the vehicle is about to retract.

When the line shape of a curve is in the form of an S, it is desirable for the vehicle driver that the lighting direction of the headlights be directed forward to the vehicle even if the near-side curve bends strongly. In this regard, it is preferable that the constant and the coefficients are set to satisfy a condition that the swing angle calculated when the curve is the S-shaped curve is smaller than the swing angle calculated when the curve is not S-shaped Curve is. Thus, it becomes possible to look at the line shape not only of the near-side curve but also of the following curve.

It is preferable that the constant and the coefficients are set to make the swing angle smaller as the curve radius becomes larger. A curve with a large radius means that the curve is gentle and that the road on which the present vehicle is traveling is close to a straight road. Accordingly, it is desirable that the illumination direction of the headlights be directed forward to the vehicle.

It is preferable that the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. A short distance means that the present vehicle has come close to the starting point of the curve. Accordingly, it is desirable that the illumination direction of the headlights be directed in the direction in which the vehicle makes a turn.

It is preferable that the constant and the coefficients are set by a test relating to a measurement, comprising the steps of: i) a real vehicle is caused to stop at any of a plurality of positions a predetermined distance to a starting point of a curve ii) each of a plurality of test riders sits on a driver's seat of the real vehicle, and iii) each test rider selects, according to a test driver's sense of vision, a swivel angle that provides the best visibility for the tester Providing test driver with respect to a line shape of the curve, from a plurality of pivoting angles, which are prepared in advance. Thus, a desired by the test driver swing angle can actually be realized.

list of figures

• 1A ein Blockschaltbild, das eine Scheinwerferbeleuchtungswinkelsteuerungsvorrichtung gemäß einem Ausführungsbeispiel der vorliegenden Erfindung veranschaulicht,
• 1B ein Blockschaltbild, das eine in der Steuerungsvorrichtung eingebaute Steuerungseinrichtung veranschaulicht,
• 2 ein Musterdiagramm, das ein bei der Berechnung eines Gradienten in einer Gradientenberechnungseinheit verwendetes Prinzip veranschaulicht,
• 3 ein Flussdiagramm, das eine Prozedur zur Steuerung eines Scheinwerferbeleuchtungswinkels veranschaulicht, die gemäß dem vorliegenden Ausführungsbeispiel ausgeführt wird,
• 4 ein Musterdiagramm, das ein Beispiel einer Experimentform veranschaulicht,
• 5A ein Beispiel der Ergebnisse eines Experiments, das für eine Linkskurve ausgeführt wird,
• 5B ein Beispiel der Ergebnisse eines Experiments, das für eine Rechtskurve ausgeführt wird,
• 6 eine beschreibende Darstellung, die Verarbeitungen zur Ausführung einer Bestimmung dahingehend veranschaulicht, ob eine Kurve eine S-förmige Kurve ist oder nicht, und
• 7A und 7B Darstellungen, die die Steuerung des Beleuchtungswinkels der Scheinwerfer zeigen.

Show it:

• 1A FIG. 4 is a block diagram illustrating a headlamp illumination angle control apparatus according to an embodiment of the present invention; FIG.
• 1B FIG. 4 is a block diagram illustrating a control device incorporated in the control device. FIG.
• 2 a pattern diagram illustrating a principle used in the calculation of a gradient in a gradient calculation unit,
• 3 FIG. 10 is a flowchart illustrating a procedure for controlling a headlight illumination angle executed according to the present embodiment; FIG.
• 4 a pattern diagram illustrating an example of an experimental form,
• 5A an example of the results of an experiment performed for a left turn
• 5B an example of the results of an experiment performed for a right turn
• 6 5 is a descriptive view illustrating processes for making a determination as to whether or not a curve is an S-shaped curve; and FIG
• 7A and 7B Illustrations showing the control of the illumination angle of the headlights.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the 1 to 3 Hereinafter, a headlamp illumination angle control apparatus according to an embodiment of the present invention will be described. In 1A FIG. 12 is a block diagram showing a headlight illumination angle control device. FIG 100 illustrated in general according to the present embodiment.

As it is in 1A is shown, includes the headlight illumination angle control device 100 basically a control device (or a processing device) 1 for carrying out various calculations, a vehicle navigation device 30 for detecting various pieces of information relating to the road on which the vehicle provided with the device is traveling, an acceleration sensor 41 for detecting an acceleration applied to the vehicle, a vehicle speed sensor 42 for detecting a speed of the vehicle based on a wheel speed, a left-side headlight 50L to light ahead to the vehicle on the left and a right-side headlight 50R to light ahead to the vehicle on the right.

The vehicle navigation device 30 includes a communication unit 31 for performing communication with a GPS satellite (GPS: Global Positioning System), a storage unit 32 (Storage device) for storing information about a current position of the vehicle with the navigation device 30 equipped vehicle passing through the communication unit 31 or information via the roads surrounding the vehicle and a destination / control unit 33 for controlling the communication unit 31 and the storage unit 32 , The storage unit 32 not only stores the road information detected by the GPS satellite, but also additionally stores information newly acquired while driving the vehicle, renewing the currently stored road information. The destination / control unit 33 detects information about a radius R [m] of a curve in which the vehicle is about to enter, or information about a distance L [m] from the current position of the vehicle to a starting point of the curve based on the current one Position of the vehicle by the communication unit 31 is captured, and the road information stored in the storage unit 32 are stored.

At the same time, the destination / control unit performs 33 a determination as to whether the curve is an S-shaped curve or not, and detects line shape information C, which are the result of the determination. The line shape information C provides information showing whether or not a curve is an S-shaped curve having specific curve characteristics such as a curvature.

Then there's how it is in 1A is shown, the vehicle navigation device 30 (Destination / Control Unit 33 ) the turning radius information R, the distance information L, and the line shape information C to the controller 1 from which the vehicle is equipped. The destination / control unit 33 When it determines that the line shape of the curve has an S-shape, it outputs "1" as the line shape information C. On the other hand, when it is determined that the curve does not have an S-shape, the determination / control unit 33 "0" as the line shape information C.

Details of the memory unit 32 Stored road information is described below. The road information includes background data and road data. The background data serves as a background for a display unit, not shown, in displaying a road map, wherein a displayed area is divided into a network, wherein each divided area called a parcel (map section) mainly includes natural terrain and rails. The road data is used to display roads in accordance with the actual roads. The road data included in a parcel includes links between nodes specifying branch points, intersection points and connection points of all roads included in the parcel. However, in the case where roads have shapes that are different from a straight line, shape supplement points between the nodes are set to simulate the actual shapes of the road connected thereto. In this case, lines connecting the nodes and the shape enhancement points, as well as the lines connecting the shape enhancement points, are called segments. In this way, a connection is made of a plurality of segments.

With reference to 6 For example, processing for determining whether or not a curve is an S-shaped curve passing through the determination / control unit is described 33 is performed. First, an S-shaped curve is made up of two curves which are connected to each other and curve in different directions. The destination / control unit 33 detects road information covering an area from the present position of the present vehicle to a point positioned forward by a predetermined distance. When the azimuth of the series of segments included in the detected road information changes from a state of change in the same direction via a state of change in a direction different from the same direction to a state of change in one reversing direction determines the determination / control unit 33 in that the curve is an S-shaped curve.

For example, in the example that curves in 6 is shown, when the vehicle is positioned at a position P1, the forwardly extending road from there to the right. Accordingly, the azimuth of segments changes sg11 . SG12 and sg13 that correspond to this part of the road, clockwise in the same direction.

However, when a turning point P0 is reached, the right turn of the road changes to a left turn. Thus, the azimuth of segments changes SG21 . SG22 and SG23 from the inflection point P0 counterclockwise in comparison to the individual segments in the previous stage. In this way, when the road has an S-shape, the azimuth of the segments of the road first changes in a certain direction. Then, when a turning point is reached, the direction of change is reversed and the azimuth changes from the point to the opposite direction. Thus, a determination as to whether the road has an S-shape or not can be made on the basis of the fact that the direction of change of the azimuth of the segments has been reversed.

Once it is determined that the road on which the vehicle is traveling has an S-shape, it is desirable that the result of the determination be maintained until the vehicle reaches the inflection point, provided that the segments are within the predetermined distance newly inserted when the vehicle is traveling, show an azimuth change in the reverse direction compared to the segments in the previous stage. It can be seen that the predetermined distance varies according to the traveling speed of the vehicle. More specifically, the predetermined distance is set to be larger as the vehicle speed becomes higher.

The left-side headlight 50L and the right-hand headlight 50R essentially use a conventionally used technique. Both headlights 50L and 50R are respectively provided with drive means (not shown) responsive to electrical control signals supplied by the controller 1 are supplied, responsive and drive associated illumination angles in the horizontal and vertical directions, which are defined with respect to the vehicle body, drive. The angles of illumination point in a direction along which light emitted by each headlamp is transmitted straight with an associated spread (see also 7A and 7B ).

More specifically, in countries with left-hand traffic for vehicles such as Japan, the left-side headlight corresponds 50L the headlamp mounted on the side of the passenger seat of the vehicle and the right-hand headlamp 50R the headlamp, which is installed on the side of the driver's seat of the vehicle. Because the acceleration sensor 41 and the vehicle speed sensor 42 Using the conventionally used technique, a detailed description thereof is omitted.

The control device 1 includes in particular, as it is in 1A shown is a central processing unit (CPU) 1A for executing various control processes and computation processing on the basis of a program described below, a memory unit including memories such as a read-only memory (ROM) 1B for storing various programs (including a part of an in 3 shown program) and data as well as a writable random access memory (RAM) 1C , an input circuit 1D comprising an A / D converter, an output circuit 1E , which includes a D / A converter, and a power supply 1F , That is, the controller 1 includes a controller system. Depending on which by the CPU 1A executed functional performance, the controller is functional in 1B shown components in which a gradient calculation unit 40 , an illumination angle calculation unit 10 and an illumination angle control unit 20 are provided. Hereinafter, these units will be used to describe the operation of the controller 1 used as needed.

As it is in 1A is shown, the control device comprises 1 the gradient calculation unit 40 , The gradient calculation unit 40 gets output values from the acceleration sensor 41 and the vehicle speed sensor 42 and at the same time computes information regarding a gradient (gradient φ) along the length of the present vehicle at the current position on the road on which the vehicle is traveling. In particular, in 2 a present vehicle 60 shown driving up a slope. As it is in 2 shown is the vehicle 60 by an acceleration G1 acting in the traveling direction and a gravitational acceleration g in the vertical direction of the vehicle 60 affects, influences. The acceleration G1 can be calculated by a vehicle speed V, which is an initial value of the vehicle speed sensor 42 is differentiated with respect to time. A symbol G shows an acceleration in directional components of the vehicle 60 on, through the accelerometer 41 is detected and with respect to a direction of travel of the vehicle 60 is arranged as a detection axis. A symbol G2 shows a heading component of the vehicle 60 whose gravitational acceleration is g. The individual components have a relationship expressed by a vector sum according to G = G1 + G2. When φ indicates a gradient of the road on the basis of the acceleration information detected by both sensors, a relationship G2 = g × sin φ is formed, which further forms a relationship expressed by the following equation (1): $$\mathrm{\phi }=\text{sin}-1\left[\left(\text{G}-\text{G}1\right)\text{/G}\right]$$

The gradient calculation unit 40 periodically executes a calculation of the gradient φ using the aforementioned equation (1), and the calculated gradient φ is applied to the illumination angle calculation unit 10 the control device 1 output. Thus, the gradient calculation unit becomes 40 , the accelerometer 41 and the vehicle speed sensor 42 a gradient information detection device produced.

As it is in 1A is shown is the illumination angle calculation unit 10 in the control device 1 provided. The Lighting angle calculation unit 10 retrieves the turning radius R, the distance L, and the line shape information C from the above-described car navigation device 30 while the gradient φ from the gradient calculation unit 40 is retrieved. Based on the various retrieved information pieces, the illumination angle calculation unit calculates 10 Swivel angle θ1 and θ2 of the left-side headlamp 50L or the right-side headlight 50R , Model equations used for the calculation of the swivel angles θ1 and θ2 will be described below. Then, the illumination angle calculation unit gives 10 the calculated swivel angles θ1 and θ2 to the illumination angle control unit 20 in the control device 1 out.

As it is in 1A is shown is the illumination angle control unit 20 in the control device 1 provided with a vehicle is equipped. As described above, the illumination angle control unit calls 20 the swing angles θ1 and θ2 from the illumination angle calculation unit 10 from. As it is in 7A is shown, when the vehicle turns to the left (to the side of the passenger seat of the vehicle when the driver steering is on the right side), the illumination angle control unit 20 a controller such that the left-side headlight 50L has the swing angle θ1 calculated on the basis of the model equation. In this case, the illumination angle control unit performs 20 a controller such that the right-side headlights 50R has a swing angle expressed by θ2 = 0. In other words, the illumination angle control unit performs 20 a controller such that the right-side headlights 50R the light throws straight ahead to the vehicle. In contrast, as in 7B is shown, when the vehicle is turning to the right (to the driver's seat side of a vehicle when driver's steering is on the right side), the illumination angle control unit 20 a controller such that the right-side headlights 50R has the swing angle θ2 calculated on the basis of the model equation. In this case, the illumination angle control unit performs 20 a controller such that the left-side headlight 50L has a swing angle expressed by θ1 = 0. In other words, the illumination angle control unit performs 20 a controller such that the left-side headlight 50L the light can throw straight ahead to the vehicle.

The model equations used for calculating the swivel angles θ1 and θ2 in the illumination angle calculation unit will be described below 10 be used.

In general, a vehicle driver visually confirms in advance the width, sharpness or the like of a turn before the driver turns the steering wheel of the vehicle or before the vehicle actually enters the turn. However, for example, during a night driving, as long as the lighting directions of the headlights are not controlled, entering a curve, in particular in such a way that after a predetermined time interval is expected by the vehicle 60 Point to reach within the headlights of the vehicle 60 illuminated area field drops, the driver of the vehicle 60 do not visually confirm the line shape of the curve. In the case where the curve is an S-shaped curve, that is, has a line shape that curves in different directions in succession, or when the curve has a slope, it is quite important for the driver to visually increase the line shape of the curve to confirm.

Also, in general, for example, a driver's seat in left-hand traffic countries is arranged on the right side of the vehicle passenger compartment using left-hand traffic. On the other hand, in countries with legal traffic, a driver's seat is generally arranged on the left side of the vehicle passenger compartment using right-hand traffic. In general, in each of the cases mentioned, the driver's seat is rarely located in the middle of the vehicle passenger compartment. That is, the driver's seat is generally arranged on one side. Further, in general, for example, the left-side headlamp of a vehicle is installed in countries having left-hand traffic so as to be oriented higher than the right-side headlamp. Thus, the light is distributed such that the illumination distance in front of the vehicle will be larger on the left side than on the right side. On the other hand, in right-hand traffic countries, the right-side headlight of a vehicle is installed so as to be more upward than the left-side headlight. Thus, the light is distributed such that the illumination distance in front of the vehicle will be larger on the right side than on the left side. Due to the lateral arrangement of the driver's seat and the different light distribution, the lighting direction in which the vehicle driver can easily make a visual confirmation of the line shape of the curve depends on whether the line shape is that of a left turn or a right turn.

The following description will be made on the assumption that the driver's seat is located on the right side of the vehicle passenger compartment and that the vehicle is driven in the left-hand traffic conditions. More specifically, if a line shape is a right-hander with a rising gradient Slope is the lighting distance in front of the vehicle, with the right-side headlight 50R is smaller than in the case of driving on a flat road. In this case, the swivel angle θ2 is set to be a large value for a possible increase in the illumination distance in front of the vehicle in conjunction with the right-side headlight 50R having. This gives the vehicle driver in particular a better possibility to visually confirm the line shape of the curve.

On the other hand, when a line shape is a right-hand curve with a decreasing gradient, the right-side headlight casts 50R (as well as the left-side headlight 50L ) originally the light in the horizontal direction. Accordingly, it does not affect the feasibility of visual confirmation of the driver of the line shape of the curve, whether the right-side headlights 50R is controlled or not controlled in accordance with the swivel angle θ2.

When a line shape is a left turn, a point on which the driver of the present vehicle pays the most attention is the curved line on the other side (forward side) of the road (the road side of the opposite lane) instead of the curved line on that side of the road ( the road side of the lane where the vehicle is driving). As described above, the left-side headlamp is 50L Installed so that it goes further up than the right-hand headlight 50R Thus, the light is distributed so that the illumination distance in front of the vehicle will be larger on the left side than on the right side. Accordingly, the point which the driver most pays attention to is sufficiently lit. In this way, in the case where the line shape of the curve curves to the side of the passenger seat, a need for control for reducing the swing angle θ1 is small. Control of the swivel angle θ1 does not help the driver to more easily achieve visual confirmation of the line shape of the curve.

wobei θ1 der Schwenkwinkel ist, α1 eine Konstante ist, β1, γ1 und δ1 vorbestimmte Koeffizienten sind, R der Kurvenradius ist, L der Abstand ist und C die Linienforminformation ist. $$\mathrm{\theta 2}=\mathrm{\alpha 2}+\mathrm{\beta 2}\times \text{R}+\mathrm{\gamma 2}\times \text{L}+\mathrm{\delta 2}\times \text{C}+\mathrm{\epsilon }2\times \mathrm{\phi }$$

wobei θ2 der Schwenkwinkel ist, α2 eine Konstante ist, β2, γ2, δ2 und ε2 vorbestimmte Koeffizienten sind, R der Kurvenradius ist, L der Abstand ist, C die Linienforminformation ist und φ Gradienteninformation ist.Under these circumstances, the illumination angle calculation unit performs 10 According to the present embodiment, a calculation of the swing angle θ1 (= θ) of the left-side headlamp 50L on the basis of the below equation (2) and a calculation of the swivel angle θ2 (= θ) of the right side headlamp 50R based on equation (3) below. $$\mathrm{<figure-callout\; id="1"\; label="\theta "\; filenames="DE102008000091B4\_0016.png,DE102008000091B4\_0017.png"\; state="\{\{state\}\}">\theta </figure-callout>}1=\mathrm{<figure-callout\; id="1"\; label="\alpha "\; filenames="DE102008000091B4\_0016.png,DE102008000091B4\_0017.png"\; state="\{\{state\}\}">\alpha </figure-callout>}1+\mathrm{<figure-callout\; id="1"\; label="\beta "\; filenames="DE102008000091B4\_0016.png,DE102008000091B4\_0017.png"\; state="\{\{state\}\}">\beta </figure-callout>}1\times \text{R}+\mathrm{<figure-callout\; id="1"\; label="\gamma "\; filenames="DE102008000091B4\_0016.png,DE102008000091B4\_0017.png"\; state="\{\{state\}\}">\gamma </figure-callout>}1\times \text{L}+\mathrm{<figure-callout\; id="1"\; label="\delta "\; filenames="DE102008000091B4\_0016.png,DE102008000091B4\_0017.png"\; state="\{\{state\}\}">\delta </figure-callout>}1\times \text{C}$$

where θ1 is the swivel angle, α1 is a constant, β1, γ1, and δ1 are predetermined coefficients, R is the curve radius, L is the distance, and C is the line shape information. $$\mathrm{\theta 2}=\mathrm{\alpha 2}+\mathrm{\beta 2}\times \text{R}+\mathrm{\gamma 2}\times \text{L}+\mathrm{\delta 2}\times \text{C}+\mathrm{<figure-callout\; id="2"\; label="\epsilon "\; filenames="DE102008000091B4\_0017.png,DE102008000091B4\_0018.png"\; state="\{\{state\}\}">\epsilon </figure-callout>}2\times \mathrm{\phi }$$

where θ2 is the swivel angle, α2 is a constant, β2, γ2, δ2 and ε2 are predetermined coefficients, R is the curve radius, L is the distance, C is the line shape information, and φ is gradient information.

The swing angles θ1 and θ2 use the forward direction as a reference, with the right side (the driver's seat side in left-hand traffic countries) being positive and the left-hand side (the passenger seat side in left-hand traffic countries) being negative. The turning radius R [m], the distance L [m], and the line shape information C in the aforementioned equations (2) and (3) become the vehicle navigation device at every predetermined time 30 detected. Similarly, the gradient φ [%] at each predetermined period of time by the gradient calculation unit 40 calculated on the basis of the above equation (1). In the gradient calculation unit 40 In conjunction with the calculation of the gradient φ [rad], the size is converted from [rad] to [%]. Values for the predetermined coefficients β1 to δ1 and β2 to ε2 and the constants α1 and α2 for weighting of these independent variables are determined by performing a multiple regression analysis on, for example, the data obtained by experiments, which is described below.

Limits θ1L and θ2L are respectively set for the swivel angles θ1 and θ2 calculated on the basis of the aforementioned equations (2) and (3). More specifically, when the swing angle θ1 calculated based on the equation (2) is smaller than the threshold value θ1L, which is expressed by "θ1 <θ1L (<0)", the left-side headlamp becomes 50L controlled in accordance with the threshold θ1L instead of the calculated swing angle. Similarly, when the swing angle θ2 calculated based on the equation (3) is larger than the threshold value θ2L expressed by "θ2> θ2L (>0)", the right-side headlamp becomes 50L controlled in accordance with the threshold θ2L instead of the calculated swing angle. The limit values θ1L and θ2L are set in consideration of the glare felt by the oncoming drivers, the glare being due to the panning of the headlights of the present vehicle. According to the present embodiment, the thresholds θ1L and θ2L are set to "-5 degrees" and "15 degrees", respectively.

When a curve in which the present vehicle is about to enter is an S-shaped curve, the lighting direction of both the left-side and the right-side headlights becomes 50L and 50R Preferably, it is controlled so as to be closer to the front-to-front direction (direct forward direction: θ = 0) in comparison with the case where it is determined that the curve is not an S-shaped curve (ie, a single curve) Vehicle is. In other words, it is preferable that each of the absolute values of the swing angles θ1 and θ2 is closer to zero. The reasons are given below. More specifically, in the case of driving on an S-shaped curve soon after completion of the near-end cornering, the vehicle reaches a starting point of the following curve. Accordingly, the driver must visually confirm the line shape of the succeeding turn in a very short time interval shortly after completion of the near-end turn and before reaching the start point of the following turn. In this case, if the swivel angle of the headlamps is controlled so as to easily allow visual confirmation of only the line shape of the near-side curve, the driver may have difficulty visually confirming the line shape of the following curve. Consequently, although the driver may have slight difficulty in visual confirmation of the near-side curve, the headlamps are preferably controlled so that the line shape of the following curve can be visually confirmed by the driver, or the entire S-shaped curve can be overlooked , Such swing angles correspond to those that can illuminate the vehicle's front-to-front direction, ie, in the case of the present embodiment, they correspond to adjustment of both the swing angle θ1 and the swing angle θ2 to values closer to zero.

When the radius of the curve in which the vehicle is about to retract becomes larger, it is preferable that the illumination directions of the left-side and the right-side headlights 50L and 50R be controlled to be closer to the front-to-front direction (θ = 0) of the present vehicle. In other words, it is preferable that the absolute value of both the swing angle θ1 and the swing angle θ2 be closer to zero. The reasons for this are described below. More specifically, a large curve radius of a curve softens the curve, allowing the curve on which the present vehicle is traveling to be closer to a straight road. That is, the angle for enabling the driver to easily perform a visual confirmation of the curve's line shape corresponds to an angle that allows the forward direction of the vehicle to be illuminated. According to the present embodiment, this corresponds to setting both the swing angle θ1 and the swing angle θ2 to a value closer to zero.

Further, when the present vehicle comes closer to a starting point of a turn, it is preferable that the lighting direction of both the left-side headlamp and the right-side headlamp 50L and 50R is turned to the direction in which the vehicle makes a turn. In other words, it is preferable that, in the case of a left turn, the swing angle θ1 (> 0) is made larger, and in the case of a right turn, the swing angle θ2 (<0) is made smaller.

The present embodiment uses these values determined by, for example, multiple regression analysis based on the data obtained by experiments described below. Accordingly, the predetermined coefficients β1 to δ1 and β2 to ε2 and the constants α1 and α2 can realize the desired swing angles θ1 and θ2.

In 3 FIG. 10 is a flowchart illustrating a procedure of the headlight illumination angle control according to the present embodiment, which is performed in a cooperative manner by the vehicle navigation device 30 and the controller 1 in the headlight illumination angle control device 100 is performed. With reference to 3 Hereinafter, the operation according to the present embodiment will be described.

First, the start of the automatic control of the headlight illumination angle is confirmed by a suitable switch or the like which is not shown. Then, in a step S100, the vehicle navigation device detects 30 the current position of the present vehicle, for example by communicating with a GPS satellite. In a subsequent step S102, the vehicle navigation device detects 30 a starting point of the curve and a radius of a curve (curve radius R), in which the vehicle is about to retract. Then, in a step S104, the vehicle navigation device detects 30 the distance information L representing a distance from the current position of the vehicle to the starting point of the curve.

After detection of the various pieces of information, the vehicle navigation device determines 30 in a subsequent step S106, whether or not the curve in which the vehicle is about to enter is an S-shaped curve. When it is determined that the curve is S-shaped Curve is ("YES" in step S106), sets the vehicle navigation device 30 in a step S108, the line shape information is set to "C = 1". On the other hand, when it is determined in step S106 that the curve is not an S-shaped curve ("NO" in step S106), the vehicle navigation device 30 in a step S110, the line shape information is set to "C = 0".

When the line shape information C has been set, the controller calculates 1 (ie the gradient calculation unit 40 ) in a step S112 the gradient information φ as described above based on the acceleration information G obtained from the acceleration sensor 41 and the vehicle speed V received from the vehicle speed sensor 42 is output using the aforementioned equation (1).

In a step S114, the controller calculates 1 (ie, the illumination angle calculation unit 10 ) the swivel angle θ1 for the left-side headlight 50L and the swivel angle θ2 for the right-side headlight 50R on the basis of the detected turning radius R, the distance information L, the line shape information C and the gradient information φ using the equations (2) and ( 3 ). In conjunction with the calculation of the swing angles θ1 and θ2, the results of the calculation are applied to the illumination angle control unit 20 output.

Then the controller determines 1 (to be more specific, the illumination angle control unit) in a step S116, whether or not the curve in which the vehicle is about to enter is a right turn. When it is determined that the curve is a right turn ("YES" in step S116), the illumination angle control unit controls 20 in a step S118, the left-side headlamp 50L in accordance with the swing angle θ1 (= 0) and the right-side headlight 50R in accordance with the swing angle θ2 calculated using equation (3). On the other hand, when it is determined in step S116 that the curve is not a right turn ("NO" in step S116), the illumination angle control unit allows 20 in that the control proceeds to a subsequent step S120.

In step S120, the illumination angle control unit determines 20 whether or not the turn into which the vehicle is about to enter is a left turn. When it is determined that the curve is a left turn ("YES" in step S120), the illumination angle control unit controls 20 in a step S122, the left-side headlamp 50L in accordance with the swivel angle θ1 calculated using equation (2) and the right-side headlamp 50R in accordance with the swing angle θ2 (= 0).

As described above, the headlight illumination angle control device calculates 100 According to the present embodiment, the swing angle θ1 when the present vehicle 60 enters a left turn, taking into account the turning radius R, the distance L and the line shape information C by a simple operation. As a result, the left-side headlight 50L is controlled so as to bring an associated illumination direction in accordance with the swivel angle θ1. If the vehicle 60 enters a right turn, the swing angle θ2 is calculated in consideration of the gradient information φ in addition to the turning radius R, the distance L and the line shape information C. As a result, the right-sided Schweinwerfer 50R is controlled so as to bring an associated lighting direction in accordance with the swivel angle θ2. In this way, an illumination angle control of the headlights 50L and 50R be realized according to the arrangement position of the driver's seat in the vehicle passenger compartment.

Further, in the headlight illumination angle control device 100 According to the present embodiment, the distance L is used as an independent variable as indicated in equations (2) and (3). Thus, the headlight illumination angle control can well in advance to the actual entrance of the vehicle 60 into a bend and not immediately before the vehicle 60 actually enters the curve, be executed. Also, in the headlight illumination angle control device 100 According to the present embodiment, the line shape information C is used as an independent variable as shown in equations (2) and ( 3 ) is displayed. Thus, the headlamp illumination angle control can correspond to the line shape of the curve in which the vehicle 60 is about to retract. Furthermore, in the headlight illumination angle control device 100 According to the present embodiment, the gradient information φ is used as an independent variable as indicated in the equation (3). Thus, the headlight illumination angle control can be adjusted according to the gradient of the curve in which the vehicle 60 is about to retract. In this way, the driver of the vehicle 60 a more precise visual confirmation of the line shape of the curve in which the present vehicle 60 is about to retract, execute.

With reference to the 4 and 5 below, an experiment for acquiring the data required to determine the predetermined coefficients β1 to δ1 and β2 to ε2 and the constants α1 and α2 in the aforementioned Equations (2) and (3) will be described. In 4 Fig. 3 is a pattern diagram illustrating an example of such an experiment. The figure includes an illustration of a road and a vehicle when viewed from above.

As it is in 4 1, a respective test driver (persons performing the test) stops in the driver's seat of the vehicle 60 sitting, the vehicle 60 at a turn start point BC and at points BC1 and BC2, the respective predetermined distances are arranged back from the turn start point BC of the turn. At the same time, at each of these stopping points, the test driver selects a swivel angle among a plurality of predetermined swivel angles so that the selected swivel angle may give the driver the feeling that visual confirmation of the curve's line shape can be most easily performed.

More specifically, it stops, as is in 4 shown is the test driver the vehicle 60 first at point BC2, which is located a second predetermined distance (eg, "27.8 m") back from the turn start point BC. The second predetermined distance corresponds to "two seconds" for the vehicle 60 are required to reach the curve starting point BC, for example, at a speed of "50 km / h".

If the vehicle 60 is stopped at the point BC2, the driver selects from the plurality of predetermined swivel angles a swivel angle, which gives the driver the feeling that a line shape of the curve is most easily confirmed visually. In particular, in the case where the curve in which the vehicle chooses 60 is about to enter, a right turn, the driver a swivel angle of four angles of "0, 5, 10 and 15 degrees" by the headlights are actually pivoted so that the selected angle can give the driver the feeling that a Line shape of the curve is the most visually confirmed. In the case where the curve in which the vehicle 60 is about to enter, is a left turn, the driver selects a swivel angle from two angles of "0 and -5 degrees" by actually swiveling the headlights, so that the selected angle can give the driver a sense that a line shape of the Curve is the most visually confirmed. Further, in the case where the curve in which the vehicle selects 60 is about to enter, an S-shaped curve, the driver a swivel angle of five angles of "-5, 0, 5, 10 and 15 degrees" by the headlights are actually pivoted, so that the selected angle to the driver Can convey the feeling that a line shape of the curve is most visually confirmed. Due to the lateral arrangement of the driver's seat in the vehicle passenger compartment, the selection of the swivel angle differs depending on the type of the curve.

After selecting a swing angle at the point BC2, the driver moves the present vehicle 60 to the point BC1 which is located a first predetermined distance (for example, "13.9 m") back from the turn start point BC. The first predetermined distance corresponds to "one second" representing the vehicle 60 needed to reach the corner starting point BC at a speed of, for example, "50 km / h". Then, the selection of a swing angle at this point BC1 is performed in a manner similar to that executed at the previous point BC2. Likewise, selection of a swing angle is similarly performed at the curve start point BC. When a tilt angle "0 degrees" is selected, an area that is considered a lighting area " A1 " in 4 is indicated by the headlights 50L and 50R illuminated. Similarly, when each of the swing angles "5 degrees" to "15 degrees" is selected, each of the areas designated as lighting areas " A2 " to " A4 "Are indicated, respectively, by the headlights 50L and 50R illuminated.

When a selection of swivel angles for a right turn as described above is completed, the series of swivel angle selection is also performed for a left turn and an S-shaped turn. It can be seen that both the turning radius R and the gradient φ between the left turn, the S-turn and the right turn are different.

In 5A a part of the results of the experiment is shown for a left turn. In 5B is shown part of the results of the experiment for a right turn. It can be seen that each of the in the column "middle angle" in both 5A as well as in 5B given values is a mean value calculated for all test drivers.

As it is in 5A As shown, when the turning radius R increases or when the curve becomes gentle, in a left turn, the line shape of the curve can be visually confirmed without the need for pivoting the headlights. Accordingly, the absolute value of the swing angle θ1 becomes small (meaning that the vehicle's front-to-front direction 60 illuminated).

Likewise, in the left turn, when the vehicle 60 comes close to the starting point BC corresponding to "point BC2 point BC1 start point BC", the headlamps are pivoted on a large scale. Accordingly, the swing angle θ1 becomes small (the absolute value of the swing angle θ1 becomes large). According to the multiple regression analysis performed for the results of the above experiment showing the results of the experiment described in 5A are indicated, the gradient φ hardly affects the swivel angle θ1. The inventors have thus confirmed that in a determination of the pivoting angle θ1, the gradient φ need not be taken into account. Meanwhile, the inventors have also confirmed that other independent variables influence the swing angle θ1 in the order "line shape information C distance L curve radius R".

As it is in 5B As shown, in a right turn similar to the case of the left turn, as the turning radius R increases, or when the turn becomes gentle, the line shape of the turn can be visually confirmed without requiring pivoting of the headlights. Accordingly, the absolute value of the swing angle θ2 becomes small (meaning that the vehicle's front-to-front direction 60 illuminated). Similarly, similar to the case of the left turn, when the vehicle 60 comes close to the starting point BC corresponding to "point BC2 point BC1 starting point BC", the pivot angle θ2 due to the need for a large pivoting of the headlight large. According to the multiple regression analysis carried out for the results of the above experiment, the results of in 5B The inventors confirmed that the swing angle θ2 is influenced by "the line shape information C the gradient φ the distance L the curve radius R" in this order.

The coefficients in equations (2) and (3) have relationships represented by "absolute value of δ1 >> absolute value of γ1> absolute value of β1" and "absolute value of δ2 >> absolute value of ε2> absolute value of γ2> absolute value of β2 "Are expressed.

It can be understood that the headlamp illumination angle control apparatus according to the present invention is not limited to the configuration exemplified in the above-described embodiment, but can be realized in the embodiment described below, for example, which is a suitable modification of the present embodiment.

In the embodiment described above, the gradient information detecting means is the gradient calculating unit 40 , the accelerometer 41 and the vehicle speed sensor 42 been prepared. Also, in the above-described embodiment, the gradient of the road in the forward direction of the present vehicle has been estimated on the basis of the gradient information of the vehicle at the present position since the gradient of the road mostly always changes gradually. However, a specific configuration of the gradient information acquirer is not limited to such a configuration.

For example, the road information contained in the storage unit 32 the car navigation device 30 are stored, may be configured to include the gradient information of each portion of the road indicated by the links and segments so that the gradient of the road in the forward direction of the present vehicle may be calculated based on the gradient information. Alternatively, the altitude information may be stored at each point of each road obtained by a GPS when the vehicle is traveling on the road, so that the gradient of the road in the forward direction of the vehicle based on the altitude information the next time if the vehicle is traveling on the same road, can be calculated. In this way, the gradient of the road in the forward direction of the vehicle can be calculated in a more accurate manner.

As it is in 6 has been determined based on the fact that the azimuth of the segments composed of fine divisions of the road which has changed in a certain direction has been reversed upon reaching a turning point has been determined that a line shape of a curve is a S-shape. However, the method for carrying out a determination is not limited to this. What matters is whether or not a line shape of a curve has an S-shape, or whether information is detected as to whether the curve has an S-shape or not. If only such a determination or detection is achieved, a selection as to the method and means for making a determination on the line shape and the method and means for acquiring the information may optionally be made. An S-shaped curve has been referred to as a curve consisting of two connected curves that curve in different directions, but an S-shaped curve may also be referred to as a curve that is a very large one short straight road section between the two curves.

As it is referring to 4 has been described in the experimental form, which is carried out in the embodiment described above and the modifications, the test driver, in the driver's seat of the vehicle 60 Take a seat, the vehicle 60 at the plurality of points BC1 and BC2, the predetermined respective distances are arranged back from the turn start point BC, and stopped at the turn start point BC. At the same time, the test driver has selected a swivel angle from a plurality of predetermined swivel angles so that the selected swivel angle may give the driver the feeling that the line shape of the curve is most visually confirmed visually. However, the experimental form is not limited to this form. For example, the number of points at which the test driver selects a swivel angle that gives the driver the feeling that the line shape of the curve is most visually confirmed visually or the speed of the present vehicle based on which the predetermined distances have been set can be increased can be changed. Alternatively, the number of selections of the swivel angle may be increased, or the test driver may voluntarily set a swivel angle and measure the swivel angle. Thus, an experimental form can be optionally selected if only a swing angle can be quantified using the curve radius R, the distance L, the line shape information C, and the gradient φ as an independent variable, so that the quantified swing angle can give the driver the feeling that the Line shape of the curve is the most visually confirmed.

In the experimental form carried out in the above-described embodiment and the modifications, a swing angle using the turning radius R, the distance L, the line shape information C, and the gradient φ has been quantized as an independent variable such that the quantified swing angle can give the feeling to the driver, that the line shape of a curve is confirmed most visually. The embodiment described above then used the multiple regression analysis for the results of the experiment to determine the predetermined coefficients β1 to δ1 and β2 to ε2 and the constants α1 and α2 in equations (2) and (3). However, the method of determining the coefficients and constants is not limited to this. Alternatively, these coefficients and constants may be determined, for example, by a simulation according to the tendency of the coefficients described above.

In the above-described embodiment and the modifications, the illumination angle calculation unit has 10 calculates a slew angle on the basis of equations (2) and (3) regardless of whether the curve into which the present Vehicle is about to enter, is a right turn or a left turn, as indicated in the processing according to step S114. Alternatively, when the curve in which the present vehicle is about to enter is a right turn, the result of the calculation for the swing angle θ1 of the left side headlamp 50L forced to zero, while the tilt angle θ2 of the right-side headlamp 50R can only be calculated on the basis of equation (3). Similarly, when the curve in which the vehicle is about to enter is a left turn, the result of the calculation for the swivel angle θ2 of the right side headlamp 50R forced to zero while the swing angle θ1 of the left-side headlamp 50L can only be calculated on the basis of equation (2). In this case, the illumination angle control unit 20 only the left-side and the right-side headlights 50L and 50R in accordance with the calculated swing angles θ1 and θ2, respectively, without making a determination on the curve in which the vehicle is about to retract.

According to the above-described embodiment and the modifications, when the curve in which the present vehicle is about to enter is a right turn, the illumination angle control unit 20 the left-side headlight 50L controlled in accordance with the swing angle θ1 (= 0), while the right-side headlight 50R is controlled in accordance with the swing angle θ2 calculated using Equation 3 as indicated in the processing of step S118. Similarly, when the curve in which the vehicle is about to enter is a left turn, the illumination angle control unit 20 the left-side headlight 50L controlled in accordance with the swivel angle θ1 calculated using equation (2) while the right-side headlamp 50R in accordance with the swivel angle θ2 (= 0) as indicated in the processing of step S122. In short, either the left-side or the right-side headlights 50L and 50R been panned. Alternatively, when the turn into which the vehicle is about to enter is a left turn, both the left and right headlights may be used 50L and 50R are controlled in accordance with the swing angles based on the equation (2). Likewise, when the turn into which the vehicle is about to enter is a right turn, both the left and right headlights may be used 50L and 50R are controlled in accordance with the swing angles based on the equation (3). Alternatively, these methods can be combined.

The above-described embodiment (including the modification) has been provided on the assumption that the driver's seat is disposed on the right side of the vehicle passenger compartment, and that the vehicle is driven under the conditions of the left-hand traffic. However, the embodiment may be applied to a case where the driver's seat is disposed on the left side of the vehicle passenger compartment and the vehicle is driven under the conditions of right-hand traffic. In this case, the left and right concepts can only be reversed. What matters is that the headlight illumination angle calculation unit calculates only the swivel angle θ on the basis of the equation (2) when the present vehicle makes a turn to the driver's seat side, and calculates the swivel angle θ only on the basis of the equation (3). when the present vehicle makes a rotation to the side of the passenger seat.

In the above-described embodiment and the modifications, the model equations for calculating the swivel angle θ have been changed depending on whether the curve in which the present vehicle is about to enter is a left turn or a right turn, that is, the present vehicle is to the side of the driver's seat or to the side of the passenger seat turns. Alternatively, the swivel angle θ may be calculated based on a single model equation.

In the above-described embodiment and the modifications, the headlight illumination angle calculation unit has calculated the swivel angle θ based on equations (2) and (3) or a single model equation using these equations as primed expressions. Alternatively to these primary expressions, the swivel angle θ may be calculated using, for example, higher order terms or non-linear functions. What matters is that the illumination angle calculation unit can only calculate the illumination angle of the headlights on the basis of not only the curve radius R and the distance L but also the line shape information C and / or the gradient information φ.

Alternatively, the illumination angle calculation unit may calculate the illumination angle of the headlights based on only the curvature radius R, the distance L and the line shape information C, omitting the gradient information φ. That is, the aforementioned equation (3) can be modified as: $$\mathrm{\theta }=\mathrm{<figure-callout\; id="2"\; label="\theta "\; filenames="DE102008000091B4\_0017.png,DE102008000091B4\_0018.png"\; state="\{\{state\}\}">\theta </figure-callout>}2=\mathrm{\alpha 2}+\mathrm{\beta 2}\times \text{R}+\mathrm{\gamma 2}\times \text{L}+\mathrm{\delta 2}\times \text{C}$$

wobei, wenn φ auf Null eingestellt wird, eine Gleichung für den Schwenkwinkel θ1 (=0) des linksseitigen Scheinwerfers 50L wie nachstehend beschrieben gebildet ist. $$\mathrm{\theta }=\mathrm{\theta 1}=\mathrm{\alpha 1}+\mathrm{\beta 1}\times \text{R}+\mathrm{\gamma 1}\times \text{L}$$

Alternatively, the illumination angle calculation unit may calculate the illumination angle of the headlights on the basis of only the curvature radius R, the distance L, and the gradient information φ, omitting the line shape information C. The above equation (3) can be modified as: $$\mathrm{\theta }=\mathrm{<figure-callout\; id="2"\; label="\theta "\; filenames="DE102008000091B4\_0017.png,DE102008000091B4\_0018.png"\; state="\{\{state\}\}">\theta </figure-callout>}2=\mathrm{\alpha 2}+\mathrm{\beta 2}\times \text{R}+\mathrm{\gamma 2}\times \text{L}+\mathrm{\epsilon 2}\times \mathrm{\phi }$$

wherein, when φ is set to zero, an equation for the swivel angle θ1 (= 0) of the left-side headlamp 50L as described below. $$\mathrm{\theta }=\mathrm{\theta 1}=\mathrm{\alpha 1}+\mathrm{\beta 1}\times \text{R}+\mathrm{\gamma 1}\times \text{L}$$

The desired goals can also be achieved through these configurations.

Various other advantages according to the above-described embodiment and the modifications can be provided.

The headlight illumination angle control apparatus having such a configuration can calculate the swivel angle θ by performing a simple operation by the primary expression according to the equation (2), which has been formed considering the curve radius R, the distance L, and the line shape information C.

In addition, the headlamp illumination angle control apparatus having such a configuration can calculate the swivel angle θ by performing a simple operation by the primary expression according to the equation (3) formed in consideration of the curve radius R, the distance L, and the gradient information φ.

For example, in left-hand traffic countries, a driver's seat is generally located on the right side of the vehicle passenger compartment using left-hand traffic. In contrast, in countries with legal traffic Driver's seat generally arranged on the left side of a vehicle passenger compartment, where a right-hand traffic is used. In each of these cases, a driver's seat is rarely located in the center of a vehicle passenger compartment, but it is generally arranged on one side.

Further, in general, for example, the left-side headlamp of a vehicle is installed in countries having left-hand traffic so as to be oriented higher than the right-side headlamp. Thus, the light is distributed so that the illumination distance in front of the vehicle on the left side becomes larger than on the right side. On the other hand, in right-hand traffic countries, the right-side headlight of a vehicle is installed so as to be more upward than the left-side headlight. Thus, the light is distributed so that the illumination distance in front of the vehicle on the right side becomes larger than on the left side.

The inventors have confirmed that, due to the lateral arrangement of a driver's seat and the different light distribution in the case where a road has a predetermined gradient, the direction in which a vehicle driver desires illumination by the headlights differs depending on whether the line shape of the curve is a left turn or a right turn.

Specifically, in the case where a curve has a line shape that curves to the driver's seat, and the gradient increases in the direction before the present position of the present vehicle (rising right turn in left-hand traffic), the distance caused by the Headlight of the vehicle is illuminated, be shorter than in the case of a flat road. In this case, setting a large swing angle may increase the possibility of increasing the distance illuminated by the headlights of the vehicle. In short, the vehicle driver may have a better chance of making a visual confirmation of the line shape of the curve.

On the other hand, in the case where a curve has a line shape that curves to the driver's seat and the gradient decreases in the direction before the current vehicle's current position (downward right turn in left-hand traffic), the headlights of the vehicle throw the light in the horizontal direction. Accordingly, it has no influence on whether or not the swivel angle of the headlamps is controlled, on the possibility for the driver to visually confirm the curve shape of the curve.

In the case where a curve has a line shape that curves to a passenger seat (left turn in left-hand traffic countries), a point that the driver most pays attention to is the curved line on the other side (forward side) of the road (the road side of the opposite lane) instead of the curved line on that side of the road (the road side of the lane on which the present vehicle is running). As described above, the headlamp is installed on the side of the passenger seat so that it is oriented further upward than the headlamp on the side of the driver's seat, thus distributing the light such that the illumination distance in front of the present vehicle on the Side of the passenger seat is larger than on the side of the driver's seat. Accordingly, the point which the driver most pays attention to is sufficiently lit. In this way, in the case where the curve has a line shape that curves to the side of the passenger seat, the requirement of control for reducing the swing angle is small. In this case, the control of the swivel angle does not help the driver to achieve a visual confirmation of the line shape of the curve much easier.

In this regard, the swivel angle of the headlamps can be accurately controlled in accordance with the above-described actual situation.

Another embodiment of the present embodiment and related modifications include an apparatus for controlling an illumination angle of headlamps installed in a vehicle, comprising: a position detecting device for a current position of the vehicle, a memory device for storing road information showing a road the vehicle is currently driving, curve keeping means for obtaining from the current position and the road information, a curve of the road, which is arranged in front of the vehicle, and for obtaining a radius of the curve, a distance obtaining means for obtaining a distance from the current position a start point of the curve, a curve determining means for determining whether or not the curve is an S-shaped curve, a line shape setting means for setting line shape information showing a line shape of the S curve in React ion to determination results of the curve determining means, a gradient obtaining means for obtaining gradient information showing a gradient of the vehicle in a direction along which the road continues, an angle calculating means for calculating an illumination angle of the headlights on the basis of the radius of the curve, the distance, the Line shape information and the Gradient information, and a controller for controlling the illumination angle of the headlights on the basis of the calculated illumination angle.

The headlamp illumination angle control apparatus having such a configuration can calculate the swivel angle θ by performing a simple operation by the primary expression of the equation formed in consideration of the curve radius R, the distance L, the line shape information C, and the gradient information φ.

For example, in left-hand traffic countries, a driver's seat is generally located on the right side of a vehicle passenger compartment using left-hand traffic. On the other hand, in countries with legal traffic, a driver's seat is generally arranged on the left side of a vehicle passenger compartment using right-hand traffic. In each of these cases, the driver's seat is rarely located in the center of a vehicle passenger compartment, but it is generally arranged on one side.

Further, in general, for example, the left-side headlamp of a vehicle is installed in countries with left-hand traffic such that it is oriented further upward than the right-side headlamp. Thus, the light is distributed so that the illumination distance in front of the vehicle on the left side becomes larger than on the right side. On the other hand, in right-hand traffic countries, the right-side headlight of a vehicle is installed so as to be more upward than the left-side headlight. Thus, the light is distributed so that the illumination distance in front of the vehicle on the right side becomes larger than on the left side. The inventors have confirmed that, due to the lateral arrangement of a driver's seat and the different light distribution in the case where a road has a predetermined gradient, the direction in which the driver desires illumination by the headlights differs depending on whether the line shape of the curve is a left turn or a right turn.

Specifically, in the case where a curve has a line shape that curves to the driver's seat and the gradient increases in the direction before the present position of the present vehicle (rising right turn in left-hand traffic countries), the distance indicated by the Headlight of the vehicle is illuminated, be shorter than in the case of a flat road. In this case, setting a large swing angle may increase the possibility of increasing the distance illuminated by the headlights of the vehicle. In short, the vehicle driver may have a better chance of making a visual confirmation of the line shape of the curve.

On the other hand, in the case where a curve has a line shape that curves to the driver's seat and the gradient falls in the direction before the present position of the present vehicle (falling right turn in left-hand traffic), the headlights of the vehicle will throw the light in the horizontal direction. Accordingly, whether or not the headlamp tilt angle is controlled does not affect the ability for the driver to visually confirm the curve shape of the curve.

In the case where a curve has a line shape that curves to a passenger seat (left turn in left-hand traffic countries), a point that the driver most pays attention to is the curved line on the other side (forward side) of the road (the road side of the opposite lane) instead of the curved line on that side of the road (the road side of the lane on which the present vehicle is running). As described above, the headlamp is installed on the side of the passenger seat so that it is oriented further upward than the headlamp on the side of the driver's seat, thus distributing the light such that the illumination distance in front of the present vehicle on the Side of the passenger seat is larger than on the side of the driver's seat. Accordingly, the point which the driver most pays attention to is sufficiently lit. In this way, in the case where the curve has a line shape that curves to the side of the passenger seat, the requirement for the control for reducing the swing angle is small. In this case, controlling the swivel angle does not help the driver achieve much easier visual confirmation of the curve's curve shape.

The present invention may be embodied in several other forms without departing from the pertinent scope. Accordingly, the present embodiments, as described, are intended to be illustrative rather than limiting, the scope of the invention being defined by the appended claims rather than the description preceding them. All changes that come within the scope of the claims, or equivalents thereof, are therefore intended to be encompassed by the claims.

An apparatus is provided to control an illumination angle of headlamps installed in a vehicle. In the apparatus, based on the current position and the road information, a curve of the road is calculated and the radius of the curve is obtained. The curve is positioned in front of the vehicle. A distance from the current position to a starting point of the curve is calculated based on the current position and the road information. A determination as to whether the curve is an S-shaped curve or not is made on the basis of the road information, and line shape information showing a line shape of the S-curve is set in response to the determination results of the curve. An illumination angle of the headlights is calculated based on the radius of the curve, the distance, and the line shape information, and the illumination angle of the headlights is controlled based on the calculated illumination angle.

Claims (39)

A device (100) for controlling a lighting angle of headlamps (50L, 50R) installed in a vehicle, comprising: a position detection device (30) configured to detect a current position of the vehicle, a memory device (32) configured to store road information showing a road on which the vehicle is currently traveling, curve keeping means (30) configured to obtain from the present position detected by the position detecting means (30) and the road information read from the storage means (32) a curve of the road ahead of the vehicle is positioned, and to get a radius of the curve, a distance obtaining means (30) configured to obtain a distance from the current position to a starting point of the curve on the basis of the current position and the road information; curve determining means (30) configured to determine whether or not the curve is an S-shaped curve based on the road information; a line shape setter (30) configured to set line shape information showing a line shape of the S curve in response to determination results of the curve determination means (30); an angle calculator (10) configured to calculate an illumination angle of the headlights based on the radius of the curve, the distance, and the line shape information, and a controller (20) configured to control the illumination angle of the headlights (50L, 50R) based on the calculated illumination angle. Device (100) according to Claim 1 wherein the distance obtaining means (30) is arranged to obtain the distance using the start point of the curve as a reference point, the line shape setting means (30) sets 1 in the line shape information when the curve is the S-shaped curve, and 0 in the line shape information when the curve is not an S-shaped curve, and the angle calculator (10) is set to set a swing angle as the illumination angle on the basis of an equation according to FIG $$\mathrm{\theta }=\mathrm{\alpha }+\mathrm{\beta }\times \text{R}+\mathrm{\gamma }\times \text{L}+\mathrm{\delta }\times \text{C}$$

where θ is the swing angle, α is a constant, β, γ and δ are coefficients, R is the curve radius, L is the distance, and C is the line shape information. Device (100) according to Claim 2 wherein the constant and the coefficients are set to satisfy a condition that the swing angle calculated when the curve is the S-shaped curve is smaller than the swing angle calculated when the curve does not have S shaped curve is. Device (100) according to Claim 3 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 3 wherein the constant and the coefficients are set to make the swing angle smaller as the curve radius becomes larger. Device (100) according to Claim 5 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 2 wherein the constant and the coefficients are set to make the swing angle smaller as the curve radius becomes larger. Device (100) according to Claim 7 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 2 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 2 wherein the constant and the coefficients are set by a test relating to a measurement, wherein: i) a real vehicle (60) is caused to stop at any of a plurality of positions (BC, BC1, BC2), the predetermined distances to one Starting point (BC) of a curve of a road to be tested, wherein the plurality of positions includes the starting point, ii) each of a plurality of test riders sitting on a driver's seat of the real vehicle (60), and iii) each test driver according to a sense of sight of the test driver Pivoting angle, which provides the best visibility for the test driver with respect to a line shape of the curve, from among a plurality of pre-prepared swing angles. A device (100) for controlling an illumination angle of headlamps (50L, 50R) installed in a vehicle a position detection device (30) for detecting a current position of the vehicle, a storage device (32) for storing road information showing a road on which the vehicle is currently traveling, curve keeping means (30) for obtaining, from the current position detected by the position detecting means (30) and the road information read from the storage means (32), a curve of the road positioned in front of the vehicle, and for obtaining a radius of the curve, a distance obtaining means (30) for obtaining a distance from the current position to a starting point of the curve on the basis of the current position and the road information, a gradient obtaining means (40, 41, 42) for obtaining gradient information showing a gradient of the vehicle in a direction along which the road continues, an angle calculating device (10) for calculating an illumination angle of the headlights (50L, 50R) based on the radius of the curve, the distance and the gradient information, and a control device (20) for controlling the illumination angles of the headlights (50L, 50R) on the basis of the calculated illumination angle. Device (100) according to Claim 11 wherein the distance obtaining means (30) is arranged to obtain the distance using the start point of the curve as a reference point, and the angle calculating means (10) is arranged to have a tilt angle as the illumination angle based on an equation $$\mathrm{\theta }=\mathrm{\alpha }+\mathrm{\beta }\times \text{R}+\mathrm{\gamma }\times \text{L}+\mathrm{\epsilon }\times \mathrm{\phi }$$

where θ is the swing angle, α is a constant, β, γ, and ε are coefficients, R is the curve radius, L is the distance, and φ is the gradient information. Device (100) according to Claim 12 wherein the constant and the coefficients are set to make the swing angle smaller as the curve radius becomes larger. Device (100) according to Claim 13 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 12 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 12 wherein the constant and the coefficients are set by a test relating to a measurement, wherein: i) a real vehicle (60) is caused to stop at any of a plurality of positions (BC, BC1, BC2), the predetermined distances to one Starting point (BC) of a curve of a road to be tested, wherein the plurality of positions includes the starting point, ii) each of a plurality of test riders sitting on a driver's seat of the real vehicle (60), and iii) each test driver according to a sense of sight of the test driver Pivoting angle, which provides the best visibility for the test driver with respect to a line shape of the curve, from among a plurality of pre-prepared swing angles. Device (100) according to Claim 12 wherein the angle calculating means (10) is arranged to calculate the swing angle based on an equation $$\mathrm{\theta }=\mathrm{\theta 1}=\mathrm{\alpha 1}+\mathrm{\beta 1}\times \text{R}+\mathrm{\gamma 1}\times \text{L}$$

where θ is the swing angle, α1 is a constant, β1 and γ1 are coefficients, R is the radius of curvature, and L is the distance when the vehicle is turning along the curve that curves to a passenger seat side, and the swing angle based on an equation according to FIG $$\mathrm{\theta }=\mathrm{\theta }2=\mathrm{\alpha 2}+\mathrm{\beta 2}\times \text{R}+\mathrm{\gamma 2}\times \text{L}+\mathrm{\epsilon 2}\times \mathrm{\phi }$$

where θ is the swivel angle, α2 is a constant, β2, γ2 and ε2 are coefficients, R is the radius of curvature, L is the distance, and φ is the gradient information as the vehicle turns along the curve leading to a Driver's seat side bends. Device (100) according to Claim 17 wherein the constant and the coefficients are set to make the swing angle smaller as the curve radius becomes larger. Device (100) according to Claim 18 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 17 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. A device (100) for controlling a lighting angle of headlamps (50L, 50R) installed in a vehicle, comprising: a position detection device (30) for detecting a current position of the vehicle, a storage device (32) for storing road information showing a road on which the vehicle is currently traveling, curve obtaining means (30) for obtaining, from the current position detected by the position detecting means (30) and the road information read from the storage means, a curve of the road positioned in front of the vehicle and obtaining a Radius of the curve, a distance obtaining means (30) for obtaining a distance from the current position to a starting point of the curve on the basis of the current position and the road information, a curve determining means (30) for determining whether or not the curve is an S-shaped curve based on the road information; a line shape setting means (30) for setting line shape information showing a line shape of the S curve in response to determination results of the curve determining means; a gradient obtaining means (40, 41, 42) for obtaining gradient information showing a gradient of the vehicle in a direction along which the road continues, an angle calculation means (10) for calculating an illumination angle of the headlights (50L, 50R) based on the radius of the curve, the distance, the line shape information and the gradient information, and a control device (20) for controlling the illumination angles of the headlights (50L, 50R) on the basis of the calculated illumination angle. Device (100) according to Claim 21 wherein the distance obtaining means (30) is arranged to obtain the distance using the start point of the curve as a reference point, the line shape setting means (30) sets 1 in the line shape information when the curve is the S-shaped curve, and 0 in the line shape information when the curve is not an S-shaped curve, and the angle calculating means is set, sets a swing angle as the illumination angle on the basis of an equation according to FIG $$\mathrm{\theta }=\mathrm{\alpha }+\mathrm{\beta }\times \text{R}+\mathrm{\gamma }\times \text{L}+\mathrm{\delta }\times \text{C}+\mathrm{\epsilon }\times \mathrm{\phi }$$

where θ is the swing angle, α is a constant, β, γ, δ and ε are coefficients, R is the curve radius, L is the distance, C is the line shape information, and φ is the gradient information. Device (100) according to Claim 22 wherein the constant and the coefficients are set to satisfy a condition that the swing angle calculated when the curve is the S-shaped curve is smaller than the swing angle calculated when the curve does not have S shaped curve is. Device (100) according to Claim 23 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 23 wherein the constant and the coefficients are set to make the swing angle smaller as the curve radius becomes larger. Device (100) according to Claim 25 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 22 wherein the constant and the coefficients are set to make the swing angle smaller as the curve radius becomes larger. Device (100) according to Claim 27 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 22 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 22 wherein the constant and the coefficients are set by a test relating to a measurement, wherein: i) a real vehicle (60) is caused to stop at each of a plurality of positions (BC, BC1, BC2) having predetermined distances to a starting point (BC) of a curve of a road to be tested, the plurality of positions Ii) each of a plurality of test drivers is seated on a driver's seat of the real vehicle (60), and iii) each test driver, according to a test driver's sense of sight, selects a swivel angle that provides the best visibility for the test driver with respect to a line shape of the curve Variety of pre-prepared swing angles selects. Device (100) according to Claim 22 wherein the angle calculating means (10) is arranged to calculate the swing angle based on an equation $$\mathrm{\theta }=\mathrm{\theta 1}=\mathrm{\alpha 1}+\mathrm{\beta 1}\times \text{R}+\mathrm{\gamma 1}\times \text{L}+\mathrm{\delta 1}\times \text{C}$$

where θ is the swivel angle, α1 is a constant, β1, γ1, and δ1 are coefficients, R is the curve radius, L is the distance, and C is the line shape information as the vehicle turns along the curve leading to a Passenger's seat side curves, and the swing angle based on an equation according to $$\mathrm{\theta }=\mathrm{\theta 2}=\mathrm{\alpha 2}+\mathrm{\beta 2}\times \text{R}+\mathrm{\gamma 2}\times \text{L}+\mathrm{\delta 2}\times \text{C}+\mathrm{\epsilon }\text{2}\times \mathrm{\phi }$$

where θ is the swivel angle, α2 is a constant, β2, γ2, δ2 and ε2 are coefficients, R is the curve radius, L is the distance, C is the line shape information, and φ is the gradient information when the vehicle is traveling along the Turn curve that curves to a driver's seat side. Device (100) according to Claim 31 wherein the constant and the coefficients are set to satisfy a condition that the swing angle calculated when the curve is the S-shaped curve is smaller than the swing angle calculated when the curve is not the S shaped curve is. Device (100) according to Claim 32 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 31 wherein the constant and the coefficients are set to make the swing angle smaller as the curve radius becomes larger. Device (100) according to Claim 34 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 31 wherein the constant and the coefficients are set to make the swing angle smaller as the curve radius becomes larger. Device (100) according to Claim 36 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 31 wherein the constant and the coefficients are set to make the swing angle larger as the distance becomes smaller. Device (100) according to Claim 31 wherein the constant and the coefficients are set by a test relating to a measurement, wherein: i) a real vehicle (60) is caused to stop at any of a plurality of positions (BC, BC1, BC2), the predetermined distances to one Starting point (BC) of a curve of a road to be tested, wherein the plurality of positions includes the starting point, ii) each of a plurality of test riders sitting on a driver's seat of the real vehicle (60), and iii) each test driver according to a sense of sight of the test driver Pivoting angle, which provides the best visibility for the test driver with respect to a line shape of the curve, from among a plurality of pre-prepared swing angles.

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